“We’ve given them time — 510 days to be exact,” Senate Majority Leader Harry Reid (D-Nev.) said on the Senate floor Wednesday. “They need to do comprehensive immigration reform, and they’ve refused to do just that.

“Executive action is important, but it’s not a substitute for legislation, and the Speaker should know that,” Reid said. “This is about where Republicans stand with the immigrant community.”

The administration is expected to issue nearly 5 million worker visas to illegal immigrants, many of whom have children who are U.S. citizens. Democrats say the administration has no choice because the House failed to take up the Senate-passed immigration reform bill that provided a pathway to citizenship, increased visas and strengthened border security.

Reid’s speech was one of many Democrats delivered on the topic Wednesday.

Obama is expected to announce his plans in a national address Thursday night.